Three dimensional additive manufacturing of metal objects by stereo-electrochemical deposition

ABSTRACT

An apparatus for stereo-electrochemical deposition of metal layers consisting of an array of anodes, a cathode, a positioning system, a fluid handling system for an electrolytic solution, communications circuitry, control circuitry and software control. The anodes are electrically operated to promote deposition of metal layers in any combination on the cathode to fabricate a structure.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims priority to U.S. patentapplication Ser. No. 15/356,210, entitled “THREE DIMENSIONAL ADDITIVEMANUFACTURING OF METAL OBJECTS BY STEREO-ELECTROCHEMICAL DEPOSITION”,filed on Nov. 18, 2016, fully incorporated by reference herein, andclaims priority to U.S. Provisional Patent Application No. 62/257,333,entitled “Apparatus for Production of Three-Dimensional Metal Objects byStereo-Electrochemical Deposition”, filed on Nov. 19, 2015, fullyincorporated by reference herein.

TECHNICAL FIELD

The present disclosure relates to an apparatus, a system and a methodfor electrically depositing conductive material from a metal saltsolution (hereinafter referred to as an electrolyte or ionic solution)on the cathode to form multiple layers using a two-dimensional array ofanodes to fabricate large three dimensional metal structures.

BACKGROUND

Additive manufacturing, also known as 3D Printing, is used for theproduction of complex structural and functional parts via alayer-by-layer process, directly from computer generated CAD (computeraided drafting) models. Additive manufacturing processes are consideredadditive because conductive materials are selectively deposited on asubstrate to construct the product. Additive manufacturing processes arealso considered layered meaning that each surface of the product to beproduced is fabricated sequentially.

Together, these two properties mean that additive manufacturingprocesses are subject to very different constraints than traditionalmaterial removal-based manufacturing. Multiple materials can becombined, allowing functionally graded material properties. Complicatedproduct geometries are achievable, and mating parts and fully assembledmechanisms can be fabricated in a single step. New features, parts, andeven assembled components can be “grown” directly on already completedobjects, suggesting the possibility of using additive manufacturingprocesses for the repair and physical adaptation of existing products.Structural and functional parts created by additive manufacturingprocesses have numerous applications in several fields including thebiomedical and aerospace industries. Traditional milling and weldingtechniques do not have the spatial resolution to create complexstructural parts that can be achieved through additive manufacturing

However, electrochemical additive manufacturing (ECAM) techniques ingeneral have several limitations such as choice of material, porosity,strength, scalability, part errors, and internal stresses. A depositionprocess must be developed and tuned for each material, and multiplematerial and process interactions must be understood. Resulting productsmay be limited by the ability of the deposited material to supportitself and by the (often poor) resolution and accuracy of the process,Widespread use of additive manufacturing techniques may be limited dueto the high cost associated with selective laser melting (SLM) andelectron beam melting (EBM) systems. Further, most additivemanufacturing devices currently in the industry use powdered metalswhich are thermally fused together to produce a part, but due to mostmetals' high thermal conductivity this approach leaves a rough surfacefinish because unmelted metal powder is often sintered to the outeredges of the finished product.

Challenges associated with the use of the ECAM processes in commercialsystems also include the slow speed of deposition with a single anode,and small (micrometer) size of parts producible by a conventional ECAMmethod. Microstructures such as metal pillars have been produced usinglocalized electrochemical deposition (LECD) process with a single anode,which is similar to ECAM, but is limited in scope to the fabrication ofsimple continuous features.

The stereo-electrochemical deposition (SED) process, an extension of theECAM process, combines two technologies: stereo-lithography andelectroplating. By inducing an electric field between the anode and thecathode, and passing metal salts between the electrodes, it is possibleto produce metal parts at the cathode rapidly at room temperature. Sincethe path of the electric field is dependent on the geometry of the partbeing built, printing of extreme overhang angles approaching 90 degreeswithout the need for a support structure, is possible.

The SED process is capable of depositing most conductive materialsincluding metals, metal alloys, conducting polymers, semiconductors, aswell as metal matrix composites and nanoparticle-impregnated materials.Electroplating and electroforming techniques have established thecapability of electrochemical processes to deposit metals over largeareas, but localizing the deposition to a controlled area has presenteda challenge.

The SED process has the potential to cheaply and quickly produce bothmetals and composite metal/polymer systems because it is a non-thermalprocess requiring relatively few moving parts and no expensive opticalor high vacuum components. Additionally, the material is deposited atomby atom resulting in good micro-structural properties (such as porosity,grain size, and surface finish) which can be controlled electronically.These characteristics allow the SED process to create certain threedimensional geometries much faster, and with higher quality thanconventional methods.

BRIEF DESCRIPTION OF THE DRAWINGS

Advantages of the subject matter claimed will become apparent to thoseskilled in the art upon reading this description in conjunction with theaccompanying drawings, in which like reference numerals have been usedto designate like elements, and in which:

FIG. 1 is a perspective view of the reactor for stereo-electrochemicaldeposition of layers of metallic material to fabricate a structure.

FIG. 2 is a front view of the reactor for stereo-electrochemicaldeposition of layers of metallic material to fabricate a structure.

FIG. 3 is a perspective view of the anode array and the controller boardof the reactor for stereo-electrochemical deposition of layers ofmetallic material to fabricate a structure.

FIG. 4 is a block diagram of the components of the process ofstereo-electrochemical deposition of layers of metallic material tofabricate a structure.

FIG. 5 is a block diagram of the process flow for stereo-electrochemicaldeposition of layers of metallic material to fabricate a structure.

FIG. 6 is a block diagram of the chemical pumping and handling systemfor stereo-electrochemical deposition of layers of metallic material tofabricate a structure.

FIG. 7A is a 3D model of a structure to be fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 7B is a top view of a structure fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 7C is a side view of a structure fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 8A is a 3D model of a structure to be fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 8B is a side view of a structure fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 8C is a top view of a structure fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 9A is a 3D model of a structure to be fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 9B is a side view of a structure fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 9C is a top view of a structure fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 10A is a 3D model of a structure to be fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 10B is a side view of a structure fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 10C is a top view of a structure fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 11A is a 3D model of a structure to be fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 11B is a side view of a structure fabricated bystereo-electrochemical deposition of layers of metallic material.

FIG. 11C is a side view of a structure fabricated bystereo-electrochemical deposition of layers of metallic material.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention relate to a controlledstereo-electrochemical deposition (SED) reactor and process performedupon a cathode to create centimeter-scale three dimensional metalobjects via electrodeposition of multiple layers using an array ofcomputer controlled anodes and a cathode. The materials are depositedlayer by layer in “slices” on the cathode to produce the desiredthree-dimensional structures. In some embodiments the plurality ofanodes are selectively movable, in other embodiments, the cathode isselectively moveable, and in other embodiments, both are moveablerelative to each other.

The system for stereo-electrochemical deposition of metal objectscomprises a chemical reactor, a chemical pumping and handling system,and an electrical control system. Each of these systems is described indetail below.

FIGS. 1 and 2 illustrate an embodiment of the chemical reactor for SEDof metal objects. Reactor 100 generally includes a chemical reactionchamber 14 configured to contain an electrolyte, or ionic solution, thatis used for the stereo-electrochemical deposition of layers of metal tofabricate a structure. During the deposition process, electrolyte iscontinuously supplied to chamber 14. The electrolyte flows throughchamber 14 and is collected for disposal or recycling. Chamber 14 isdisposed on a structural support 38, which may be made of metal orplastic or other suitable materials known to those of ordinary skill inthe art. In an embodiment, a linear actuator 30 to control the movementof cathode 26 is disposed on chamber 14 on the side opposite to wherestructural support 38 is located.

In one embodiment, chamber 14 is rectangular in cross-section and ismade of a chemical resistant polymer material, glass, or otherchemically-resistant metal, plastic or ceramic material capable ofcontaining the solution. In an alternate embodiment, chamber 14 may becircular or another geometry in cross-section, composed of glass or analternate chemical resistant polymer, metal or ceramic material capableof containing the solution. Persons of ordinary skill in the art wouldunderstand however that chamber 14 may have be configured according tomany different designs suitable to carry out the SED process accordingto the invention. Conventional reactor design considerations would applyto the geometry, size and materials of construction.

Chamber 14 is provided with an inflow fluid port 20 a to allow freshelectrolyte from the chemical pumping and handling system to enterchamber 14. Chamber 14 is also fitted with an outflow fluid port 20 b toallow the used electrolyte to exit chamber 14 into a waste handling orrecycling system (not shown). In other embodiments, chamber 14 may befitted with a plurality of inflow fluid ports and outflow fluid ports.The inflow and outflow ports may be positioned on the same side wall ofchamber 14, or they may be positioned on different side walls of chamber14, or may be included as part of the design of the anode or the cathodeassemblies.

Electrolyte from tank 59 is pumped into chamber 14 by fluid pump 52(FIG. 6) through the inflow fluid port 20 a. Fluid port 20 a is disposedon a fluid flow guide 22 a. In an embodiment, fluid ports connect thechamber to the rest of the chemical pumping and handling systemcomponents (pump, quick disconnect fittings, valves, tank, etc.). In anembodiment, fluid flow guide 22 is disposed on the side walls of chamber14 to direct the flow of the electrolyte to the fluid guide vanes 34 andanode array 10.

As illustrated in FIG. 3, anode array 10 is disposed on fluid guidevanes 34. Anode array 10 is completely submerged in the electrolyteduring the operation of the SED process. Fluid guide vanes 34 providecompressive force between the anode array 10, the gasket 12, and theanode flange 32. Fluid guide vanes 34 also direct the flow of theelectrolyte over anode array 10, laminarizing the flow over the anodesto provide for even deposition of metal layers according to theinvention. During the operation of the system, electrolyte is pumpedinto the chamber as described above, and pumped out of chamber 14through flow guides 22 b and the outflow fluid port 20 b into a waste orrecycling system.

As illustrated in FIG. 3, anode array 10 is positioned within fluidguide vanes 34 of chamber 14 of the reactor 100. In an embodiment, anodearray 10 may have a rectangular shape with a plurality of elements thatdefine a pattern of arrangement of the individual anode elementsresponsible for depositing metal layers in desired shapes. Anode array10 may be made of a combination of plastic, ceramic, polymer, refractoryor transition metal, semiconductor, carbon, and/or dielectric material.In other embodiments, array 10 may have different geometric designs toconnect individual anodes in different patterns such as rectangular,circular, hexagonal, or oval. Within the anode array, multiple insulatedanode conductive elements made of platinum or another conductivesubstance are generally disposed on and secured to the overall anodearray 10. In an embodiment, each individual exposed anode element ofanode array 10 is made of platinum wire.

In FIG. 3, an anode array interface board 16 is electrically coupled toarray 10 to provide electrical power to array 10 through conventionalribbon cables or other suitable connection means known in the art. Anodearray interface board 16 also receives current and voltage informationfrom cathode 26 through the current sensor 46 and the voltage controller63 both embedded in the control board 400 (FIG. 4). Board 16 acceptselectronic information as well as electrodeposition power (current) in acorresponding fashion to the anode array patterns dictated by addressingsystem 57 and current controller 64 respectively (FIG. 4). In otherembodiments, some or all of the functions of the control board 400 maybe integrated into the anode interface board 16.

In other embodiments, a printed circuit board with the same pattern ofopenings as anode array 10 may be used to connect each of the anodeelements to a power source. In an embodiment, array 10 comprises 64dimensionally stable platinum anodes made from 24-gauge (0.5 mmdiameter) 3 mm long platinum wire, such as, for example, 95% Pt 5% Ruwire. Anode elements of the anode array 10 are secured into fitted viasin anode array interface board 16. In an embodiment, anode arrayinterface board 16 is built on a FR4 2.0 mm thick double-sided PCB Boardfabricated with 0.3 mm trace width.

As illustrated in FIGS. 1-3, gasket 12 is disposed between array 10 andfluid guide vanes 34, to contain the electrolyte in the chemical reactorand prevent leaks. In an embodiment, gasket 12 is made from a chemicallyresistant elastomeric polymer. In an embodiment, an anode flange 32 isdisposed underneath the anode array 10. In an embodiment, anode array 10is secured by screws on the bottom to chamber 14, and these screws aretightened to provide clamping force to compress gasket 12. In anotherembodiment, the clamping force is provided by other mechanical devices,such as spring tension, or a full-length threaded rod which exert forceon the chamber 14 downward towards the anode array 10 to compress gasket12 between the anode array 10 and the bottom of chamber 14. In otherembodiments not shown in FIGS. 1-3, the anode array may be coupled to anelectro-mechanical positioning system so that the position of the anodearray relative to the cathode may be changed according to the desiredposition for the metal layer deposition step of the fabrication.

Referring again to FIGS. 1-3, a cathode 26 comprising one or morecathodic conductive materials is disposed within chamber 14 and isspaced from anode array 10. In an embodiment, cathode 26 may be disposedabove anode array 10. In an embodiment, cathode 26 comprises a 9×9 mmsquare graphite rod with a polished anode-facing end. Cathode 26 isattached to the anode-facing surface of cathode slider 24. Cathodeslider 24 mechanically fixes the position of cathode element 26 withinchamber 14 during operation of the system and deposition method andhouses a chemically resistant electrical connection between the cathodeand control board 400. In an embodiment, cathode slider 24 is made ofplastic, for example, polypropylene with an electrical contact made ofchemically resistant conductive material, for example titanium,chromium-alloy, stainless steel, or carbon. A cathode slider linkage 28connects the cathode slider 24 to the linear actuator 30 which controlsthe movement of cathode slider 24 within chamber 14.

In an embodiment, in which the cathode can be selectively positionedrelative to the anode array, the distance between cathode 26 and anodearray 10 is controlled by movement of the cathode slider 24. In anembodiment, cathode slider 24 is driven by a position actuator 30, whichis controlled by a position controller 56 located on the control board400 (FIG. 4). In an embodiment, position actuator 30 may be anon-captive leadscrew stepper motor such as, for example, Haydon KerkMotion Solutions, Inc.'s switch and instrument stepper motor. In anembodiment, position controller 56 may be a stepper motor driver suchas, for example, a Pololu Corporation's A4988 stepper motor driver. Theposition of cathode 26 within chamber 14 is detected through a cathodeposition sensor 62 (not shown) located near the top of chamber 14, andis communicated to microcontroller 50 (FIG. 4.) In an embodiment,cathode position sensor 62 may be a mechanical waterproof micro-switchsuch as, for example, a Yueqing Dongnan Electronics Co., Ltd. WS1Waterproof Micro Switch 5A

FIG. 4 illustrates the level of chemical exposure of various componentsof the SED system 1000. SED system 1000 comprises chemically exposedcomponents module 500, chemically immersed components module 600, and acontrol module 400. Chemically immersed components of module 600 shouldbe composed of engineered plastics (such as PET, PP, FEP, PTFE, certainepoxies, etc.), noble metals, certain carbon compounds, or other highlychemical resistant materials. Chemically exposed components of module500 should be waterproof and have no exposed solder or metal partsexcept stainless steel. Components of the control module 400 are notexposed to chemicals and do not need to be made of chemical resistantmaterials.

FIG. 4 also illustrates the operation of the electrical control system1000 which enables stereo-electrochemical deposition of layers ofmetallic material according to an embodiment of the invention. Controlboard 400 provides regulated power to all electromechanical componentsof the reactor for the SED process (such as the pump, the stepper motorand the stepper motor driver), as required by the software configurationof the system and the Multiple Independently Controlled Anode (MICA)algorithm.

As illustrated in FIG. 4, microcontroller 50 interfaces with a storagemodule 42 to receive machine configuration information and layer slicedata. Storage module 42 may be a personal computer or any device capableof storing and passing layer slice data to the microcontroller 50. In anembodiment, the storage module 42 is composed of a Secure Digital cardreader and card. In another embodiment, the storage module 42 iscomposed of a serial interface to a personal computer which deliverslayer files to the microcontroller 50.

Some example computer devices include desktop computers, portableelectronic devices (e.g., mobile communication devices, smartphones,tablet computers, laptops) such as the Samsung Galaxy Tab®, Google Nexusdevices, Amazon Kindle®, Kindle Fire®, Apple iPhone®, the Apple iPad®,Microsoft Surface®, the Palm Pre™, or any device running the Apple iOS®,Android® OS, Google Chrome® OS, Symbian OS®, Windows Mobile® OS, WindowsPhone, BlackBerry® OS, Embedded Linux, Tizen, Sailfish, webOS, Palm OS®or Palm Web OS®.

In an embodiment, microcontroller 50 may be an Arduino Megamicrocontroller board. Microcontroller 50 receives electronic inputcorresponding to the position of cathode 26 from cathode position sensor62. Microcontroller 50 receives electronic input from current sensor 46corresponding to the total deposition current flowing through thecathode element. Using this electronic input, microcontroller 50determines through computations whether to move the cathode, increase ordecrease voltage to the anode elements, or turn various anode elementson or off in order to facilitate accurate and speedy deposition of thecurrent layer slice.

Microcontroller 50, in an embodiment, directs the operation of thecathode z-axis position controller 56 based on information received fromthe current sensor 46, from the position sensor 62, and based on theactive/inactive state of each anode in the addressing system 57. Thisinformation is used by the MICA software algorithm running onmicrocontroller 50 to determine the appropriate cathode z-axis positionof cathode 26. Cathode position controller 56 controls the movement oflinear actuator 30 which is mechanically linked to, and moves, cathode26 via cathode slider linkage 28 and cathode slider 24 inside chamber14, as was described above. (FIGS. 1 and 2).

Microcontroller 50 controls the operation of fluid pump 52 and valves 54to direct the flow of the electrolyte solution through chamber 14 of thereactor 100. In an embodiment, valves 54 comprise electrically actuated,chemically resistant solenoid valves. In an embodiment, the fluidpumping speed may be varied at regular intervals to clear out bubbleswhich may have formed on the anode after a length of time of steadystate deposition. In another embodiment, the fluid pumping speed may bekept at a steady rate and ultrasonic agitation may be provided into thereaction chamber 14 in order to clear out bubbles.

Anode array 10 is controlled by microcontroller 50 through an addressingsystem 57, which in turn supplies data to the current controller 64. Thesource voltage to the current controller 64 is also adjustedcontinuously by microcontroller 50 through a voltage controller 63 whichreceives an analog signal from the microcontroller 50 through theDigital-to-Analog converter (DAC) 61. According to embodiments of theinvention, current controller 64 may be a NPN or PNP transistor, aSziklai Pair compound transistor comprising one NPN transistor and onePNP transistor, a n/p-channel Field Effect Transistor (FET), or anydevice which has the ability to deactivate or limit the current flowingto individual anodes in the anode array when the current exceed acertain threshold limit.

In an embodiment, the addressing system 57 may be a shift register orlatching circuit composed of one or more transistors,serial-in/parallel-out (SIPO), parallel-in/serial-out (PISO) or otheraddressing components which convert a multiplexed digital signal into ade-multiplexed digital or analog signal. In an embodiment, the voltagecontroller 63 may be a Linear Technologies LM317 adjustable linearvoltage controller, buck, boost or single-ended primary-inductorconverter (SEPIC) converter, or any adjustable voltage power supply ofsufficient current capacity to supply all anode elements of anode array10. In an embodiment, DAC 61 is composed of a LC or RC filter circuitintended to convert digital PWM signals from the microcontroller into ananalog input for the voltage controller 63. In other embodiments, DAC 61may be omitted if a digital voltage controller 63 is used.

The metal deposition model according to the present invention is derivedfrom Faraday's first and second laws of electrolysis. The amount ofchemical change produced by current at an electrode-electrolyte boundaryis proportional to the quantity of electricity used. The amounts ofchemical changes produced by the same quantity of electricity indifferent substances are proportional to their equivalent weights.

These laws can be expressed as the following formula:

$m = {\left( \frac{Q}{F} \right)\left( \frac{M}{z} \right)}$

Where m is the mass of the substance liberated at an electrode in grams;Q is the total electric charge passed through the substance; F isFaraday's constant (96485 C/mol⁻¹); M is the molar mass of the substancein AMU (for example, for copper this value is 63.55); z is the valenceof the ions of the substance (for example, for copper (II) sulfate thisvalue is 2).

For variable electric current deposition (as utilized by SED) Q can bedefined as:Q=∫ ₀ ^(t) I(τ)dτwhere t is the total electrolysis time, and I(τ) is the electric currentas a function of the instantaneous time tau τ. d(τ) is the computationtime for each iteration of the algorithm.

Substituting mass for volume times density, and adding the integralcharge for Q produces:

${\rho\; V} = {{\rho\;{Ad}} = \frac{\int_{0}^{t}{{Idt}*M}}{z*F}}$Where ρ is the density of the material (8.96 g/cm³^3 for copper); A isthe area of a single deposit on the cathode (note: this is NOT the sameas the anode area) d is the distance (z-height) of the deposited columnof material.

Rearranging the equation and expanding the area term results in thefollowing equation:

$d = \frac{\int_{0}^{t}{{Idt}*M}}{{zF}\;{{\rho\pi}\left( r_{eq} \right)}^{2}}$

This equation gives a model for the z-height produced at a singlecircular anode pin as a function of deposition current, equivalentradius of the cathode deposit, and known physical and chemicalconstants.

The equivalent radius of a deposit produced on the cathode, R_(eq) ismodeled as a function of the “throw angle” (λ), the working distance(dw) and the anode radius (r) which is approximated by the followingfunction:r _(eq) =r+d _(w)*tan(λ)

According to an embodiment, the throw angle (λ) was empiricallydetermined to best fit with observed results at 28° for a standard acidcopper solution consisting of 900 g distilled water, 250 g coppersulfate pentahydrate, and 80 g sulfuric acid by weight. Those ofordinary skill will be able to determine the throw angle (λ) for otherelectrolytes and reactor configurations, if required.

Microcontroller 50 uses the above mathematical model to produce anoverall process flow which compares the expected deposition rate onanode array 10 with the actual rate of deposition as detected by thecathode position sensor. In one embodiment, the expected deposition rateon anode array 10 is compared with the actual deposit height by“shorting” successive anodes in anode array 10 and raising the cathodeto the next layer only when all anodes have been shorted. In anembodiment, the microcontroller 50 attempts to have the system forstereo-electrochemical deposition of layers of metallic materials tofabricate a structure by creating an even layer of metal deposits acrosseach of the active anodes of anode array 10 by allowing the metaldeposited material to grow from the cathode element 26 until the metaldeposited material reaches anode array 10. When the metal materialdeposited on the cathode element contacts the anode element, the metalmaterial will short circuit cathode to anode. The current controller 64detects the short circuit on each individual anode of anode array 10 andlimits that individual anode's current to a predetermined value, or cutsoff current to that individual anode element altogether. Thisinformation is detected by microcontroller 50 through the MICA algorithmby analyzing input from the current sensor 46.

In an embodiment, the Multiple Independently Controlled Anodes (MICA)software performs the following steps:

1. Detect deposit layer height (zero the cathode);

2. Detect uneven deposits, adjust individual anode pulse-widthmodulation (PWM) to compensate;

3. Raise cathode to appropriate working distance;

4. Recalculate constants for new working distance and the of activeanodes in the anode array;

5. Begin printing layer with n active anodes;

6. Sense total current;

7. If current is below desired amperage as predicted by model, raisevoltage;

8. If current is above desired amperage, lower voltage;

9. If current derivative is above threshold (possible short), return tostep 2, above;

10. If predicted deposit height exceeds threshold, return to step 1,above;

11. Otherwise, run the Ziegler-Nichols method of tuning a proportionalintegral derivative controller (PID controller) to maintain anodedeposition current at appropriate level—return to step 6.

FIG. 5 illustrates the logic flow process of the controlledstereo-electrochemical deposition according to the mathematical modeldescribed above. The overall process may be described as “deposit,verify, adjust, and repeat.”

Typical process parameters for the SED process, in an embodiment, arelisted below:

Parameter Value Voltage Dynamically adjusted via Zieglar-Nichols PID(1.8-3.8 V) Pulse period DC Electrolyte Copper sulfate hexahydrate (250g), Sulfuric acid (80 g), water (900 g) Anode 64 Pt-Ru (95/5) pins (0.5mm diameter) Cathode 9 mm × 9 mm graphite block Working distance 0.6-0.9mm Target deposition current 1.38-6.0 mA/pin (65-285 A/dm²)

The process described above functions well for electrodeposition oftwo-dimensional objects and can be accomplished without any CAD,stereolithography modeling or slicing software.

However, in order to accomplish true three-dimensional (stereo)-electrodeposition (SED) of functional parts, additional steps are required.

FIG. 5 depicts the process for SED of multiple layers to fabricate threedimensional structures according to an embodiment. In step 500, a CADmodel of the desired product is exported to a stereolithography (STL)file. In step 501, the STL file is exported to an open source digitallight projection (DLP)-based stereo-lithography (SLA) 3D printercontroller (slicing) software application, to produce layer slices. Inan embodiment, the slicing software may be Creation Workshop v1.0.0.13from Envision Labs. In step 502, layer slice information is processedinto anode array signals by the slicing software. Layer sliceinformation may be output as PNG files along with a descriptive G-codefile with information regarding layer width and number of slices. Instep 503, anode array signals are sent to microcontroller 50. A machineconfiguration file (.mcf) may be created for microcontroller 50 to allowmicrocontroller 50 to determine the physical parameters of thecontrolled stereo-electrochemical deposition reactor.

In step 504, microcontroller 50 loads new layer information based onlayer slices received in step 503. In step 505, microcontroller 50detects the deposit height of cathode 26 for deposition of the new layerof metallic material. During operation of the SED process,microcontroller 50 may detect any uneven deposits of new material andadjust the overall anode bias voltage to maintain target depositionrate.

In step 506, microcontroller 50 adjusts the position of cathode 26 to anappropriate working distance from anode array 10 for deposition of thenew layer of material. In step 507, microcontroller 50 computes theparameters of the operation of the SED system based upon the newposition of cathode 26 determined in step 506. In step 508,microcontroller 50 causes a layer to be deposited. Microcontroller 50continuously monitors the drive current, bias voltage and active anodesof anode array 10 to maintain overall system efficiency.

As illustrated in steps 509 and 510, if microcontroller 50 detects thatthe cathode current is above the target anode element amperage times thenumber of active anodes, voltage to entire anode array is lowered bymicrocontroller 50, or microcontroller 50 deactivates anode elements asneeded to eliminate shorted anode elements. As illustrated in steps 513and 514, if microcontroller 50 detects that the drive current is belowthe desired amperage as predicted by the model, voltage to the anodearray is increased.

As illustrated in steps 511 and 512, if microcontroller 50 detects thatall anodes of anode array 10 have been deactivated, the deposition ofthe layer is deemed complete. The process returns to step 504 fordeposition of the next layer, and repeats until the structure iscompleted.

FIG. 6. illustrates an embodiment of the chemical pumping and handlingsubsystem which enables the stereo-electrochemical deposition process. Atank 59 is connected to the system through quick disconnect fittings 60to route the flow of electrolyte to chamber 14 through filter 58 andvalves 54. The flow of electrolyte then returns through the pump 52 andanother set of quick disconnect fittings 60 and returns to the tank 59or to a waste management system. In an embodiment, a filter 58 may beused, such as, for example, a chemical resistant polypropyleneT-strainer, 200 mesh from McMaster Carr (8680T21). The electrolyte ispropelled through the system by fluid pump 52 such as HYCX10inkpump-12VDC. The flow of the electrolyte through the system iscontrolled using fluid valves 54, which may be chemically resistantvalves, such as, for example, Parker Series 1 Miniature Inert PTFEIsolation Valves. Microcontroller 50 controls the operation of pumps 52and valves 54. Power supply 40 provides the necessary power to run thesystem. In an embodiment, power supply 40 may be a Toshiba 15V 3.0 mmPA3283U-1ACA adapter/charger.

The following is a material selection guide which sets forth expectedmodel compatibility, chemical prices, deposition rates and materialproperties for the various metals which could be deposited according tothe embodiments of the invention:

Feedstock Price Deposition Electrical Thermal Melting ($/kg metal ionspeed Conductivity Conductivity Point Models supported eq.) (% of Cuspeed) (% of Cu) (% of Cu) (° C.) Gold All Spot + 20% 25% 65% 83% 1064Silver All Spot + 30% 10% 106%  106%  962 Zinc All $45 150%  29% 29% 420Zn/Fe/Co/Ni All $50 10-35% 10-28% 5-20% 300-750 Alloys Copper All $50100%  100%  100%  1085 Nickel A1200-2500 $50 40% 22% 24% 1455 Tin All$50 15% 15% 17% 231 Pure Iron All $50 300%  17% 20% 1538 Stainless 316LA1200-2500 $60  5-10% 2.5%   4% 1400 Aluminum A1200-2500 $120 15% 60%50% 660 w/Mods Titanium A1200-2500 $160  5-20%  4%  5% 1668 w/ModsPolypyrrole A1200-2500 $80 1-2% 0.000084%     0.05%   150 Tungsten A2500$80  5-10%  8% 28% 2800 Carbide MMC BNNT A2500 $850 4-5%  1%  3% 1400Reinforced 316L SGCNT/Cu A2500 $550 90% 140%  110%+ 1085 Matrix

Below is a list of potentially deposited materials and ranges ofallowable, and preferred, process conditions for each deposit material,identifying the metals that can be deposited and the various reagentsand additives used in the SED process for each deposit material. In thechemical compositions listed below, all compounds are assumed to besoluble in an aqueous solution:

Copper

-   -   Allowable chemicals/concentrations:        -   Copper sulfate, hexahydrous or anhydrous (0-350 g/L).            Concentrations are for the hexahydrous case        -   Sulfuric acid (0-270 g/L)        -   Copper chloride (0-100 g/L)        -   Copper Fluoroborate (0-450 g/L)        -   Fluoroboric acid (0-30 g/L)        -   Boric acid (0-30 g/L)        -   Copper pyrophosphate (22-38 g/L) and corresponding salt:            potassium or sodium pyrophosphate (150-250 g/L), as well as            a source of nitrate (5-10 g/L) and ammonia ions (1/3 g/L).        -   Copper cyanide (15-75 g/L) and corresponding cyanide salts            or Rochelle salt.    -   Allowable Additives        -   benzotriazole, cadmium, casein, cobalt, dextrin,            dimethylamino derivatives, disul-fides, 1,8-disulfonic acid,            disodic 3,3-dithiobi spropanesulfonate, 4,5-dithiaoctane-1,8            disulfonic acid, dithiothreitol, ethylene oxide, gelatin,            glue, gulac, lactose benzoylhydrazone, 2-mercaptoethanol,            molasses, sulfonated petroleum, o-phenanthroline,            polyethoxyether, polyethylene glycol, polyethylene imine,            poly N,N0-diethylsaphranin, polypropylene ether, propylene            oxide, sugar, thiocarbamoyl-thio-alkane sulfonates, and            thiourea.    -   Allowable Temperature range        -   18° C.-60° C.    -   Allowable Voltage range        -   0.2V-6V    -   Allowable Current range        -   1.6 A/dm² to 260 A/dm²    -   Preferred conditions for the SED process        -   Electroplating solution: Copper sulfate, 250 g/L (saturated            solution at room temperature). Sulfuric acid 0-40 g/L.        -   Additives: Sodium dodecyl sulfate (SDS) 600 mg/L        -   Temperature: 25° C. (room temperature)        -   Voltage: 2.8-3.2V        -   Current: 200-500 A/dm², 75% duty cycle square wave

Nickel

-   -   Allowable Chemicals/concentrations:        -   Nickel sulfate, hexahydrous (225-400 g/L).        -   Boric acid (0-45 g/L)        -   Nickel Ammonium Sulfate (0-45 g/L)        -   Nickel Chloride (30-450 g/L)        -   Nickel fluoroborate (0-300 g/L)        -   Zinc sulfate (0-30 g/L)        -   Ammonium sulfate (0-35 g/L)        -   Sodium thiocyanate (0-15 g/L)        -   Zinc chloride (0-30 g/L)        -   Ammonium chloride (0-30 g/L)        -   Phosphoric or phosphorous acid (0-50 g/L)    -   Allowable Additives:        -   Sulfur containing compounds and surfactants        -   Benzene, naphthalene and other “brighteners”    -   Allowable Temperature range:        -   25° C.-80° C.        -   Temperature control should be controlled to within +/−2° C.    -   Allowable Voltage range:        -   0.2-1.0V, 4V possible in high frequency pulsed deposition    -   Allowable Current range:        -   0.5-10 A/dm²    -   Allowable Preferred conditions for the SED process        -   Electroplating solution: Nickel sulfate, 240 g/L. Nickel            chloride, 45 g/L. Boric acid, 30 g/L.        -   Additives: Sodium dodecyl sulfate (SDS) 600 mg/L        -   Temperature: 25° C. (room temperature)        -   Voltage: 4V @ 75% duty cycle 100 ns pulse period        -   Current: 10 A/dm² (target)

Silver

-   -   Allowable Chemicals/concentrations:        -   Silver metal (0-120 g/L)        -   Silver cyanide (0-150 g/L)        -   Silver nitrate (0-450 g/L)        -   Potassium cyanide (45-160 g/L)        -   Potassium carbonate (15-90 g/L)        -   Potassium nitrate (0-60 g/L)        -   Potassium hydroxide (0-30 g/L)    -   Allowable Additives:        -   Glucose, tartaric acid, Rochelle salt, ethyl alcohol,            potassium nitrate, hydrazine, hydrazine sulfate, ammonia,            ethylenediamine, 3,5-diiodotyrosine, Na-2-3-mercaptopropane            sulfonate, and other “stabilizers”.    -   Allowable Temperature range:        -   25° C.-50° C.    -   Allowable Voltage range:        -   4-6V (strike voltage), 0.1-2V plating voltage, pulse            deposition may be possible    -   Allowable Current range:        -   0.5-10 A/dm²    -   Preferred conditions for the SED process (process may be        modified to reduce cyanides due to their toxicity)        -   Electroplating solution: Silver nitrate or silver            cyanide-based solution.        -   Additives: Sodium dodecyl sulfate (SDS) 600 mg/L, other            additives TBD        -   Current: 10 A/dm² (target)

Zinc

-   -   Allowable Chemicals/concentrations:        -   Zinc cyanide (0-60 g/L)        -   Sodium cyanide (0-40)        -   Sodium hydroxide (0-80 g/L)        -   Sodium bicarbonate/carbonate (0-15 g/L)        -   Sodium sulfide (0-2 g/L), catalytic        -   Zinc chloride (0-130 g/L)        -   Nickel chloride (0-130 g/L)        -   Potassium chloride (0-230 g/L)    -   Allowable Additives:        -   Thiosemicarbazide and their thiosemicarbazone derivatives            such as Thiosemicarbazide (TSC), Acetophenone (AcP),            Cinnamaldehyde (CnA), Crotonaldehyde (CrA), Furfuraldehyde            (FrA), Salcylaldehyde (SaA), Acetophenonethiosemicarbazone            (ApTSCN), Cinnamaldehydethiosemicarbazone (CnTSCN),            Crotonaldehydethiosemicarbazone (CrTSCN),            Furfuraldehydethiosemicarbazone (FrTSCN), Salcylaldehyde            thiosemicarbazone (SaTSCN)        -   (a) poly(N-vinyl-2-pyrrolidone), and p0 (b) at least one            sulfur-containing compound selected from compounds of the            formulae:            RS(R′O)n H(I) or S—[(R′O)n H]2  (II)        -   Polyvinyl alcohols, polyethyleneimine, gelatin and peptone    -   Allowable Temperature range:        -   25° C.-40° C.    -   Allowable Voltage range:        -   3-18V (strike voltage), pulse deposition may be possible    -   Allowable Current range:        -   0.1-50 A/dm²    -   Preferred conditions for the SED process (will not deposit pure        zinc due to toxicity and difficulty of using DSA anode        tech—instead will attempt deposit zinc/nickel alloys)        -   Electroplating solution: Zinc chloride, 120 g/L. Nickel            chloride 120 g/L. Potassium chloride, 230 g/L        -   Additives: Sodium dodecyl sulfate (SDS) 600 mg/L, polyvinyl            alcohol MW 5k-20k Dalton, as well as polyethyleneimine,            gelatin and peptone, 0.1-3 g/L.        -   Temperature: 25° C. (room temperature)        -   Current: 5 A/dm² (target)

Iron and ferrous alloys

-   -   Allowable Chemicals/concentrations (for iron metal):        -   Iron sulfate (0-300 g/L) or Iron ammonium sulfate        -   Ammonium sulfate (0-120 g/L)        -   Ferrous chloride (0-300 g/L)        -   Calcium chloride (0-335 g/L)        -   Potassium chloride (0-180 g/L)        -   Ammonium chloride (0-20 g/L)        -   Iron fluoroborate (0-226 g/L)        -   Sodium chloride (0-10 g/L)    -   Allowable Chemicals/concentrations (for selected stainless steel        alloys),        -   Iron sulfamate, Cobalt sulfamate, ammonium metavanadate,            boric acid, sodium tetraborate, ascorbic acid, saccharin,            SDS, potassium dichromate (˜300 g/L), nickel sulfate (˜80            g/L), Iron sulfate (˜50 g/L), Glycine (˜150 g/L)    -   Allowable Chemicals/concentrations (for selected high-toughness        boron steel alloy)        -   Ferrous chloride (˜200 g/L)        -   Malic acid (0.6 g/L)        -   Boric acid (40 g/L)        -   Dimethylamineborane (3 g/L)    -   Allowable Additives:        -   SDS        -   1 g/L of condensate of sodium naphthalene sulfonate and            formaldehyde    -   Allowable Temperature range:        -   25° C.-110° C.    -   Allowable Current range:        -   1-400+A/dm²    -   Preferred conditions for the SED process (iron chloride baths        will be avoided due to the tendency for ferric chlorides to        form, and due to the extremely corrosive nature of the chloride        plating solutions)        -   Electroplating solution: Iron fluoroborate (225 g/L), Sodium            chloride (0-10 g/L). Boron-alloy and stainless solutions may            be pursued at a later date        -   Additives: Sodium dodecyl sulfate (SDS) 600 mg/L, 1 g/L of            condensate of sodium naphthalene sulfonate and formaldehyde        -   Temperature: >50° C. (target)        -   Current: 10 A/dm² (target)        -   Working distance: TBD (suspected to be around the same            distance as the radius/half width of the anode)

Aluminum

-   -   May employ ionic liquids, aluminum chlorides, aluminum        chloride-butylpyridinium chlorides (BPC), aluminum        chloride-trimethylphenylammonium chloride (TMPAC) and/or        aluminum flourobororides    -   Deposition potential likely ˜-0.4-1.0V

Polymer deposition and polymer matrix composites (PMC)

-   -   Allowable Chemicals/concentrations (for iron metal):        -   Polyaniline        -   Polypyrrole (monomer 3 g/L)        -   polythiophene        -   polyphenylenevinylene        -   Acetonitrile        -   Methanol        -   Oxcalic acid        -   Sodium salicylate    -   Allowable Additives:        -   Lithium perchlorate (as a catalyst for deposit adhesion),            Tiron (0.05 M)    -   Allowable Voltage range:        -   0.4-1.0V    -   Allowable Current range:        -   0.1 A/dm²    -   Preferred conditions for the SED process        -   Electroplating solution: Pyrrole, 3 g/L. Lithium            perchlorate, concentration TBD. Tiron (15.7 g/L), composite            materials may be added to the electroplating bath such as:            single walled or multi-walled functionalized carbon            nanotubes, silica fibers, aerogels, or amorphous powders,            boron, boron nitride, silicon carbide, or other high            strength ceramic materials, graphene or graphene oxide, etc.        -   Additives: Sodium dodecyl sulfate (SDS) 600 mg/L, 1 g/L of            condensate of sodium naphthalene sulfonate and formaldehyde.        -   Dopants: Tosyl chloride, tosylic acid.        -   Temperature: >50° C. (target), max temp will depend on            chamber construction mats.

Metal matrix composites (MMC)

-   -   Allowable Chemicals/concentrations:        -   All allowable chemicals and concentrations listed in the            specification. Functionalized/solvated nanomaterials or high            strength ceramic fibers such as: single walled or            multi-walled functionalized carbon nanotubes, silica fibers,            aerogels, or amorphous powders, boron, boron nitride,            silicon carbide, or other high strength ceramic materials,            graphene or graphene oxide, etc.        -   Multi-walled carbon nanotubes (MWNTs) may be added in            concentrations as high as 4 g/L    -   Allowable Additives:        -   Polycyclic acid, MHT, Polyacrylic acid, SDS    -   Allowable Voltage range:        -   0.4-5.0V    -   Allowable Current range:        -   0.1 A/dm²    -   Preferred conditions for the SED process        -   Electroplating solution: Pyrrole, 3 g/L. Lithium            perchlorate, concentration TBD. Tiron (15.7 g/L), composite            materials may be added to the electroplating bath such as:            single walled or multi-walled functionalized carbon            nanotubes, silica fibers, aerogels, or amorphous powders,            boron, boron nitride, silicon carbide, or other high            strength ceramic materials, graphene or graphene oxide, etc.        -   Additives: Sodium dodecyl sulfate (SDS) 600 mg/L, 1 g/L of            condensate of sodium naphthalene sulfonate and formaldehyde            Temperature: >50° C. (target), max temp will depend on            chamber construction mats.

Below is a list of electrolytes which may be used to carry the metal,semimetal and electroconductive monomer ions:

-   -   Water        -   Allowable temperatures: 18° C.-95° C.        -   Allowable voltage range: 0.2-7.2V        -   Allowable current range: 0.1-1000 A/dm²        -   Potentially deposited materials: All potentially deposited            materials listed in the specification, in addition to Al,            Pd, In, Sb, Te, Ga, Si, Ta, and Ti, as well as Metal Matrix            Composites (MMC) and codeposited Polymer Matrix Composites            (PMC).    -   Ionic liquids        -   Based on: Ethyl ammonium nitrate, alkyl-pyridinium chloride,            2-hydroxy-N,N,N-trimethylethanaminium, dimethylsulfoxide, or            alkyl-arylimidazolium.        -   Containing an anion group such as: Hexafluorophosphate,            Bis(trifluoromethylsulfonyl) amide,            Trispentafluoroethyltrifluorophosphate, Trifluoroacetate,            Trifluoromethylsulfonate, Dicyanoamide, Tricyanomethide,            Tetracyanoborate, Tetraphenylborate,            Tris(trifluoromethylsulfonyl)methide, Thiocyanate, Chloride,            Bromide, Tetrafluoroborate, Triflate, etc.        -   Containing a cation groups such as: Choline, Pyrrolidinium,            Imidazolium, Pyridinium, Piperidinium, Phosphonium            (including Tri-hexyl-tetradecylphosphonium), Pyrazolium,            Ammonium, Sulfonium, etc.        -   Allowable temperatures: 0° C.-300° C.        -   Allowable voltage range: 0.2-7.2V        -   Allowable current range: 0.1-1200 A/dm²        -   Potentially deposited materials: All listed in 0095, in            addition to Al, Pd, In, Sb, Te, Ga, Si, Ta, Mg, and Ti, as            well as Metal Matrix Composites (MMC) and codeposited            Polymer Matrix Composites (PMC).

FIG. 7A illustrates a 3D model of a structure to be fabricated bystereo-electrochemical deposition of layers of copper performed underthe following conditions:

Parameter Value Voltage Dynamically adjusted via Zieglar-Nichols PID(1.8-3.8 V) Pulse period DC Electrolyte Copper sulfate hexahydrate (250g), Sulfuric acid (80 g), water (900 g) Anode 64 Pt-Ru (95/5) pins (0.5mm diameter) Cathode 9 mm × 9 mm graphite block Working distance 0.65 mmTarget deposition current 5.0 mA per pin

FIG. 7B is a top view of a structure fabricated bystereo-electrochemical deposition of layers of copper for 6 hours underthe conditions described above.

FIG. 7C is a side view of a structure fabricated bystereo-electrochemical deposition of layers of copper for 6 hours underthe conditions described above.

FIG. 8A illustrates a 3D model of a structure to be fabricated bystereo-electrochemical deposition of layers of copper performed underthe following conditions:

Parameter Value Voltage Dynamically adjusted via Zieglar-Nichols PID(1.8-3.8 V) Pulse period DC Electrolyte Copper sulfate hexahydrate (250g), Sulfuric acid (80 g), water (900 g) Anode 64 Pt-Ru (95/5) pins (0.5mm diameter) Cathode 9 mm × 9 mm graphite block Working distance 0.7 mmTarget deposition current 5.2 mA per pin

FIG. 8B is a side view of a structure fabricated bystereo-electrochemical deposition of layers of copper for 8 hours underthe conditions described above.

FIG. 8C is a top view of a structure fabricated bystereo-electrochemical deposition of layers of copper for 8 hours underthe conditions described above.

FIG. 9A illustrates a 3D model of a structure to be fabricated bystereo-electrochemical deposition of layers of copper performed underthe following conditions:

Parameter Value Voltage Dynamically adjusted via Zieglar-Nichols PID(1.8-3.8 V) Pulse period DC Electrolyte Copper sulfate hexahydrate (250g), Sulfuric acid (80 g), water (900 g) Anode 64 Pt-Ru (95/5) pins (0.5mm diameter) Cathode 9 mm × 9 mm graphite block Working distance 0.86 mmTarget deposition current 2.1 mA per pin

FIG. 9B is a side view of a structure fabricated bystereo-electrochemical deposition of layers of copper for 50 hours underthe conditions described above.

FIG. 9C is a top view of a structure fabricated bystereo-electrochemical deposition of layers of copper for 50 hours underthe conditions described above.

FIG. 10A illustrates a 3D model of a structure to be fabricated bystereo-electrochemical deposition of layers of copper performed underthe following conditions:

Parameter Value Voltage Dynamically adjusted via Zieglar-Nichols PID(1.8-3.8 V) Pulse period DC Electrolyte Copper sulfate hexahydrate (250g), Sulfuric acid (80 g), water (900 g) Anode 64 Pt-Ru (95/5) pins (0.5mm diameter) Cathode 9 mm × 9 mm graphite block Working distance 1 mmTarget deposition current 3.1 mA per pin

FIG. 10B is a side view of a structure fabricated bystereo-electrochemical deposition of layers of copper for 97 hours underthe conditions described above.

FIG. 10C is a top view of a structure fabricated bystereo-electrochemical deposition of layers of copper for 97 hours underthe conditions described above.

FIG. 11A illustrates a 3D model of a structure to be fabricated bystereo-electrochemical deposition of layers of copper performed underthe following conditions:

Parameter Value Voltage Dynamically adjusted via Zieglar-Nichols PID(1.8-3.8 V) Pulse period DC Electrolyte Copper sulfate hexahydrate (250g), Sulfuric acid (80 g), water (900 g) Anode 64 Pt-Ru (95/5) pins (0.5mm diameter) Cathode 9 mm × 9 mm graphite block Working distance 0.8 mmTarget deposition current 2.6 mA per pin

FIG. 11B is a side view of a structure fabricated bystereo-electrochemical deposition of layers of copper for 110 hoursunder the conditions described above.

FIG. 11C is a side view of a structure fabricated bystereo-electrochemical deposition of layers of copper for 110 hoursunder the conditions described above.

In the description above and throughout, numerous specific details areset forth in order to provide a thorough understanding of an embodimentof this disclosure. It will be evident, however, to one of ordinaryskill in the art, that an embodiment may be practiced without thesespecific details. In other instances, well-known structures and devicesare shown in block diagram form to facilitate explanation. Thedescription of the preferred embodiments is not intended to limit thescope of the claims appended hereto. Further, in the methods disclosedherein, various steps are disclosed illustrating some of the functionsof an embodiment. These steps are merely examples, and are not meant tobe limiting in any way. Other steps and functions may be contemplatedwithout departing from this disclosure or the scope of an embodiment.

We claim:
 1. An apparatus comprising: a reaction chamber configured toretain an ionic solution that can be decomposed by electrolysis; ananode array containing a plurality of anodes stationary with respect toone another, the anode array disposed in the reaction chamber andconfigured to be immersed in the ionic solution such that the pluralityof anodes are in fluid contact with one another through the ionicsolution, and such that the plurality of anodes cause a deposition of aunitary layer structure or a series of unitary layer structures; acathode disposed in the reaction chamber and configured to be immersedin the ionic solution such that the cathode is in fluid contact with theplurality of anodes through the ionic solution; a system forelectro-mechanically positioning either the anode array, the cathode, orboth to control the distance between the anode array and the cathode; atleast one sensor for measuring an electrical current flowing through theplurality of anodes, the cathode or both; and, a microcontroller,coupled to the system for electro-mechanically positioning either theanode array, the cathode, or both, coupled to the at least one sensor,and coupled to a source of layer slice information, programmed withinstructions that when executed by the microcontroller cause themicrocontroller to: (i) control the current applied to each anode of theplurality of anodes; and (ii) using the sensor current measurement,control the electro-mechanical positioning of the anode array, or thecathode, or both to control the distance between the anode array and thecathode during an electrolytic decomposition of the ionic solution tocause the deposition of the unitary layer structure or the series ofunitary layer structures.
 2. The apparatus of claim 1, wherein the anodearray has a geometrical shape that is chosen from the group consistingof hexagonal, rectangular, square, or circular geometrical shapes. 3.The apparatus of claim 2, wherein the anode array is constructed upon aprinted circuit board, doped or undoped semiconductor, or other means ofseparating conductive elements from one another and aligning them in apre-determined pattern.
 4. The apparatus of claim 2, wherein the anodearray is connected electrically to, or disposed upon an integratedcircuit, semiconductor, or combination of conductive and insulativeelements meant for biasing the plurality of anodes.
 5. The apparatus ofclaim 1, wherein each of the plurality of anodes has an exposed surfacehaving a geometric shape chosen from the group consisting of a hexagon,a rectangle, a triangle, a square, or a circle.
 6. The apparatus ofclaim 1, wherein the plurality of anodes is arranged in rows in theanode array.
 7. The apparatus of claim 1, wherein each of the pluralityof anodes is insulated from one another and is biased individually. 8.The apparatus of claim 1, wherein each of the plurality of anodes isinsulated from one another and is biased in groups of anodes.
 9. Theapparatus of claim 1, wherein each of the plurality of anodes isconstructed out of a material resistant to physical depletion throughelectrolysis.
 10. The apparatus of claim 1, wherein theelectro-mechanical positioning system includes an actuator and a controlsystem in communication with the microcontroller.
 11. In a reactionchamber configured to retain an ionic solution that can be decomposed byelectrolysis, the reaction chamber having an anode array containing aplurality of anodes stationary with respect to one another, and acathode disposed in the reaction chamber such that the plurality ofanodes and the cathode are all in fluid contact through the ionicsolution, a method comprising: a) at a microcontroller programmed withinstructions that when executed by the microcontroller cause themicrocontroller to control the current applied to each anode of theplurality of anodes, receiving layer slice information about a structureto be fabricated in the reaction chamber layer by layer by electrolyticdecomposition of the ionic solution; b) under the control of themicrocontroller, providing to the reaction chamber the ionic solutioncontaining metal ions to be deposited on the cathode according to thereceived layer slice information for the layer to be fabricated; c)under the control of the microcontroller, processing the layer sliceinformation for the layer to be fabricated causing the adjusting of thedistance between the anode array and the cathode; d) under the controlof the microcontroller, further adjusting the distance between theplurality of anodes and the cathode at a rate proportional to measuredvalues of the electrical current flowing through the plurality ofanodes, the cathode or both, the rate of adjusting the distanceresulting in a substantially constant distance between the growing layerbeing deposited on the cathode and the anode array; (e) under thecontrol of the microcontroller, processing the layer slice informationfor the layer to be fabricated, depositing the layer to be fabricated onthe cathode by providing individualized current to each of the pluralityof anodes thereby causing an electrochemical reaction at the cathode tocause the deposition of a unitary layer structure or a series of unitarylayer structures; and, (f) repeating steps (a) through (e) for eachlayer of the structure to be fabricated until all layers are deposited.12. The method of claim 11, wherein adjusting the distance between theanode array and the cathode includes moving the anode array relative tothe cathode by using an electro-mechanical positioning system undercontrol of the microcontroller.
 13. The method of claim 11, whereinadjusting the the distance between the anode array and the cathodeincludes moving the cathode relative to the anode array by using anelectro-mechanical positioning system under control of microcontroller.14. The method of claim 11, wherein adjusting the the distance betweenthe anode array and the cathode includes moving the cathode and theanode array by using an electro-mechanical positioning system undercontrol of the microcontroller.
 15. The method of claim 11, whereindepositing the layer to be fabricated on the cathode includes depositingat least one material selected from group consisting of gold, silver,zinc, Zn/Fe/Co/Ni alloys, copper, nickel, tin, iron, stainless steel,aluminum, titanium, polypyrrole, silicon, tungsten carbide MMC, PMC,BNNT Reinforced 316L, and SWCNT/Cu matrix.
 16. The method of claim 11,wherein the temperature of the ionic solution is maintained between 0°C. and 300° C.
 17. The method of claim 11, wherein the current appliedto the plurality of anodes is maintained between 0.1 A/dm² and 1200A/dm².
 18. The method of claim 11, wherein the voltage applied betweenany single anode and the cathode is maintained between 0.2 V and 7.2 V.19. The method of claim 11, wherein repeating steps (a) through (e)includes repeated deposits of the same material.
 20. The method of claim11, wherein repeating steps (a) through (e) includes depositing adifferent material than the first deposition at least once.